Under the connecticut compromise, who was responsible for electing members of the upper house of legislation?

 Each state's legislature would elect members to the upper  chamber of the legislature--the Senate.

Context/detail:

The Great Compromise was a measure decided during the United States Constitutional Convention in 1787.  The Great Compromise resolved a dispute between small population states and large population states.  The large population states wanted representation in Congress to be based on a state's population size. (This was the essence of the Virginia Plan.) The smaller states feared this would lead to unchecked dominance by the big states; they wanted all states to receive the same amount of representation.  (This was the New Jersey Plan.)

The Connecticut compromise, often called "The Great Compromise," created a bicameral (two-chamber) legislature, with different rules for representation in each chamber. Representation in the House of Representatives would be based on population.  In the Senate, all states would have the same amount of representation, by two Senators.

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